thirdchildhood

iTrader: (6)

It sounds like he is being straight up about the top speed. A 502 or 496 HO will get you an honest 73 mph. A 525 like mine runs 83-85. Bjorn in Sweden is running 112 mph with a pro-charged 540. And, yes, many of us are running XR/Imco -2 drives including myself and the boat in the video. Check this out: https://www.youtube.com/watch?v=mq6bSy4lfnU&feature=youtu.be

DBleil89

First I'm curious if these speed numbers are on salt or fresh water. Not for the Sweden, he is legit fast as he'll salt or fresh water. Salt is supposed to be a couple mph faster. Also if you are looking for speed and stability at that speed you need to raise your prop up. I have a motor i put together. It should be 550-600hp. It's going to the dyno this winter to tune it and verify hp. I have seen an honest 75 gps in fresh water. With the stock bravo 1 with a nose cone. The boat is pretty unsettling at that speed with the stock drove height. Yes hydraulic steering should help a ton. But raise the prop up and get less drag in the water. You get more speed and better ride at that speed. Just my .02. I'm no expert I just know what I am seeing and trying.

Pat McPherson

My boat has a bone stock B1 drive with the prop shaft quite low (about 7" below the bottom).
I do not have external steering but will say that my gimbal and other steering components are in solid, like new condition.
I run a 4 blade Merc Rev 4 25P Prop and the boat is rock solid trimmed up at WOT and 70+mph.
She does not handle as well with a 3 blade but will go about +1mph at WOT.
The numbers I posted from my ride last night are on the CT river (fresh water).
Lots of talk last night with my crew about upgrades I've thought about doing ie. short lower, cam swap for more HP, external steering... Thinking the boat runs so well, leave it as is...

Pat McPherson

I've not ever seen a difference running in salt vs. fresh. Maybe over 75mph you need a short lower but I'm not convinced. At over 500HP you should blow past 75 in a 22 Donzi. What are the other details of your setup? what prop? what engine rpm? Is the hull straight? Nose cones don't always help and can hurt...

thirdchildhood

iTrader: (6)

I would do the Imco -2" shorty and full steering. Zeiger offers a complete kit as they make, or used to make, the factory Donzi steering.

DBleil89

The steering is on the list for the winter. It's a must if running anything over 70. Also so is an interior since mine is pretty rough. I only have 12-15 hours on the motor. It picks up a little rpm and speed. each time I run it. The imco -2 is on the list for most likely next winter. The motor is not completely dialed in, I'm sending it to a dyno shop this winter to get it tuned and verify the h.p.

The hull is straight and slightly strengthed. It's an 87 that looks like a black hawk. I bought my VIP to swap the bravo off it (that already had the nose cone) with the alpha off the Donzi. The motor is a Gen VI 454 bored and stroked to a 496. It's running a mild cam and 10.3:1. Aluminum heads and stainless marine exhaust. Edelbrock air gap intake with an 850dp. With the thunderbolt ignition. I just did a fun run with 21 other boats and I was by far the smallest. I was in the middle of the pack with top speed. I can run at 3600 and get 55-60 depending on my load and gas amount. I'm spinning a 27p mirage plus at 4800 rpm and getting 75.4 on gps. Like I said it still has a good bit put tinkering to be done.

Pat McPherson

I believe your boat would be more stable with a different prop.
I love the Rev 4 but they only go up to 25P.
If you have the $ a Hydro P5X is also a great prop for old school V bottoms with deep drives.
Lots of guys running modified (for extra bow lift) B1s ; a stock B1 is not a great choice.

Pat McPherson

I agree those would be the best upgrades for a 22C if one is looking to push well past the 70mph mark or runs hard in the rough. Personally, I'm not ready to spend the $7-8K on my boat; I don't push her hard vary often.

DBleil89

I agree there are better props, this is one a guy was nice enough to let me borrow. His buddy let me borrow a 28p bravo 1 and it just slipped to much. I got 72 at 5000 rpm. The drive high is just to low for that prop. I'm most likely going to try and get a used 27p mirage plus this winter so I can keep tweaking. Sadly like most everyone. I don't make a lot of money to be throwing into the boat. I basically save my side job money and use that to upgrade the donzi. The bravo 1 out drive is fine for what I do with it. I run on the river, it's pretty flat. If it gets choppie I slow down. I don't come out of the hole hard, there is no need. The boat planes right off at 2,200rpm. Also I only run at wot for a couple minutes at a time max. I know when I'm doing 35 and just gradually put the throttle down it pulls like no other. The acceleration is a thrill alone. I like just being able to cruse in the 2 barrel and be doing 55-60. It makes runs down the river pretty short. During the fun run the other week I had a full tank and 3 adults in the boat. We drive for 3 hours and I used less then 25 gallons of gas. I was doing 3600 with some wot when I was in front or far enough behind. Also at wot it's not chine walking or anything it just feels pretty loose. Once it's trimmed right it actually starts going a bit right because of the prop rotation.

Pat McPherson

I've had good luck with the Turbo 1 3blade props for deep drives. I've run them on TRS and Bravo. Turbo Props are also less $$ than Merc or at least they were. Not a big fan of the Mirage + stock out of the box. I do wish Merc made a 27P Rev 4...